tree 03904fe5d2a9434851868cff9f31f97b47493ea8
parent 648e465f54f538a133fb31c9b1e3b487a6f2ca7c
author Nick Vatamaniuc <vatamane@apache.org> 1488308422 -0500
committer Nick Vatamaniuc <vatamane@apache.org> 1488308422 -0500

Restore adding some jitter-ed sleep to shard scanning code.

Otherwise a large cluster will flood replicator manager with potentially
hundreds of thousands of `{resume, Shard}` messages. For each one, it
would try to open a changes feed which can add significant load and has
been seen in production to hit varios system limits.

This brings back the change from before the switch to using mem3 shards
for replicator db scans.

Also adds a few tests.

COUCHDB-3311